Drill extractor



5;. NIPKEN ETAL DRILL EXTRACTOR May 8, 1956 3 Sheets-Sheet 1 Filed Jun 21, 195] Snventors ELEANOR NIPKEN, and WALTER NIPKEN (Ittornegs May 8, 1956 E. NIPKEN ET AL 2,744,311

DRILL EXTRACTOR Filed June 21, 195] 5 Sheets-Sheet 2 Zhmentors ELEANOR NIPKEN, and WALTER NIPKEN (Ittornegs May 8, 1956 E. NIPKEN ETAL DRILL EXTRACTOR 5 SheeLS-S'neei 3 Filed June 21, 195] Ihwentor ELEANOR NIPKEN, and B WALTER NIPKEN Gttornegs 2,744,311 DRILL EXTRACTOR Eleanor Niplren and Walter Nipken, Irvington, N. L, as-

signors to The Walton Company, West Hartford, Conn., a corporation of Connecticut Application June 21, 1951, Serial No. 232,831

' 8 Claims. (Cl. 29-240) This invention relates to an extracting or fishing'tool and, more particularly, to a tool for extracting'the embedded portions of brokentwist drills, auger bits, spiral taps and other spirally fluted instruments commonly used indrilling or boring operations.

It is the general aim of the invention to provide anextracting tool having improved operating characteristics to facilitate the, removal of embedded portions of broken drills and the like a-ndwhich is readily adjustable to suit the tool to variousoperating conditions such as, for example, when a relatively small section of the drill is embedded deeply within a bore as compared to a larger section embedded a short distance in a bore.

Another object of the invention is to provide an easily operable extracting tool which does not require the services of a skilled mechanic.

Another object of the invention is to provide an extracting tool having the foregoing operating characteris. tics and comprising elements which may be simply and economically fabricated and assembled'and which may be individually replaced in the event of breakage or wear without requiring an entirely new tool assembly.

Other objects will be in partobvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application of which will be indicated in the appended claims.

In the drawings: f r I I Fig. 1 is a side elevational view of an extracting tool constructed in accordance with the present invention;

Fig. 2 is a transverse sectional view taken as indicated by the line 22 of Fig. 1; I Fig. 3 is a cross-sectional view in the plane of thelongitudinal axis of the tool shown in Fig. l and showing the tool operatively associated with the embedded portion of a broken drill; i

Fig. 4 is arr-exploded view of the tool shown in Fig. 1; Fig. 5 is an elevational view partly in cross section of a modifiedbushing or housing construction for the tool shown in the foregoing figures;

,Fig. 6 is a side elevational view with parts shown in cross section for greater detailof a. modified extracting tool constructed in accordance with the present invention;

Fig. 7 is-a top plan view of the bushing or housing utilized in the modification shown in .Fig. 6;

Fig. 8 is a view similar toFi'g. 6 but showing an ad- I may be guided into. the hole to engage and loosen the drill section upon manipulation of the tool.

then, theextracting tool comprises a housing or bushing A, a guide B, and extracting means C.

Referring now to the embodiment shown in the first 7 four. figures of the drawings, it will be seen that the bushing or housing A is an elongated member having angularly related outer surfaces 10 prescribing in the presend of the housing which terminates in the upper end portion of the housing. The housing A is provided with a reduced lower end portion iii-which is externally threaded to receive hexagonal nut 18 for a purpose to be described in greater detail hereinafter.

The guide B is formed similarly to a twist drill having a pair of spiral flutes 2t) and corresponding spiral ribs 22. However, the guide differs from a drill in that it has no shank or cutting tip, the lower end 24 and the upper end 26 of the guide being fiat and normal to the longitudinal axis thereof. The guide B is disposed within the bore 12 in the housing A in sliding relation and in turn slidably receives in its flutes the extracting means C which comprises a pair of spirally wound wires.

Each of the extractor wires C in the illustrative disguide B. The lower end, portion 30 of each of the extractor wires is pointed or tapered inwardly so that the lower extremity of the wire will taper toward the longitudinal 'axis of the guide B when the extractor wire is disposed in one of the flutes of the guide. The upper end portion '32 of the extractor 'wires'is bent so as to extend radially outwardly from the guide when the wire is within a flute 20 on the guide.

In the assembled relation of the tool, the extractor wires are disposed within the flutes on the guide in the same relative position so that the radially extending end portions 32 extend outwardly in diametrically opposed positions in substantially the same transverse plane. The wire stock utilized for the extractor wires is of a size permitting complete disposition of the wires Within the flutes, the outer surface of the wires being the same distance from the axis of the guide aslthe periphery of the ribs 22.

After assembling the extractor wires on the guide, the guidemaybe slidably inserted within the bore 12 in the housing with the-radial extensions 32 on the extractor wires sliding within the opposed housing slots 14. The

sliding fit of the guide and wires within the bore and the The invention is illustrated in the accompanying draw- I sliding fit of the radial extensions 32 within the slot permits'longitudinal adjustment of the elements. However,

assembly of the nut 18 on the housing provides means for retaining the elements in any desired longitudinal position. When the nut 18 is threaded on the reduced end portion 16, the split lower end of the housing closes upon the guide ribs and outer surface of the wires to retain be fabricated in any desired length. The length of the Patented May 8 1955,

In general guide and extractor wires to a great extent determines the adjustability of the tool to suit various operating con ditions. One operating condition is illustrated in Fig. 3 wherein the tool is shown disposed for removal of a broken drill section D which is embedded within a drilled hole or well 34 in a work piece W. One successful operating technique comprises sliding the assembled guide and extractor wires into the housing and then positioning the housing over the hole 34, as shown in Fig. 3. Then the guide B is pressed downwardly in the housing into the hole 34 until the bottom 24 of the guide engages the top of the broken drill section D. The guide is then held in the afore described position and the extractor wires are lowered into the bore 34 by pressing the radial extensions 32 downwardly in slots 14 which causes rotation of the housing A about the guide B. The guide B will support and guide the extractor wires during downward movement so that the lower extremities 30 will be threaded in the flutes of the drill section D. In order for initial threading to occur, it may be necessary to rotate the guide so that the flutes in the guide will align with the flutes in the drill section. The pointed or tapered ends 30 on the extractor wires facilitate threading of wires and also tend to push aside the chips which remain along the flutes of the drill section D. It is not necessary in all cases to extend the extracting wires to the bottom of the drill as shown in 3 but removal of the broken drill is facilitated by so doing. Thereafter, the nut 18 is tightened upon the reduced threaded end 16 to secure the extracting wires,

guide and housing against relative movement to eachother.

The broken drill section D is then loosened within-the bore 34 by fitting a wrench about the housing A and rotating the same in a direction counter to the pitch or thread of the drill. In manipulating the wrench, the same should be pressed downwardly against the upper surface of the nut 13 to prevent climbing movement of the extracting wires within the flutes of the drill section D. Rotation of the extracting tool without permitting the same to climb will transmit the rotative forces through the wires C to the drill D and effect loosening of the drill section. After loosening, the tool and drill section D may be removed from the bore 34 in many cases with a straight pull but, in some cases, the tool and drill must be rotated as the assemblage is withdrawn from the hole.

Fig. illustrates a modified construction for the housing which is utilized in the aforedescribed extractor. The modification comprises substituting an annular collar 36 for the nut 18. in the modified construction, the reduced end 16 is cylindrical and not provided with an external thread. The collar 36 has a central bore which slidably receives the reduced end and the collar carries a set screw 38 frr engagement with the cylindrical end or shank 16. The collar is preferably fitted over the end of the bushing with the set screw normal to the plane of the slots 14 so that the slotted end of the housing -is partially closed upon advancing'the set screw. The operation of the tool with the modified housing is the same as previously described.

Another modification of the extracting tool is shown in Figs. 6 and 7 wherein the construction of the bushing A is such as to dispense with the previously described nut 18 and the collar 36. In this embodiment, the housing A Y is fabricated from a generally cylindrical body 40 having diametrically opposed flats 42 for receiving a wrench or similar tool. The flats do not extend to the bottom of the body 40, thereby defining radially extending flanges 44. The irc lii ei housing is not provided with the previously described slots but is provided with a central bore 46 serving the same purpose as the bore 12 in the first described construction. The guide B and extracting wires C are inserted within bore 46 with the radial extensions 32 on the extracting wires spaced above the top of the housing. The housing carries a pair of longitudinally spaced diametrically opposed set screws 48'which may i be advanced inwardly to engage the extracting wires and the guide to retain the same in adjusted positions relative to each other and to the bushing.

The modified form of the extracting tool shown in Figs. 6 and 7 is operated in a manner similar to the manner of operation of the previously described extracting tool. The only diflerence in the operating procedure occurs in setting the housing relative to the other elements by means of set screws 48 rather than by the use of a nut or collar. The last described modification may be preferred because of its simplified construction and manner of operation and due to its simplicity the tool can be fabricated most economically.

Figs. 8 and 9 disclose an additional form of the invention wherein the extracting wires C are modified as well as the housing A. The modification to the extracting wires occurs at the upper end thereof in that the previously described radial projections 32 are dispensed with. The upper ends of the wires are twisted upon each otherand secured as by welding or the like within a cavity 50 in a cap 52. Thus, the wires are retained as a unit for threading on the flutes of the guide B.

The modification to the housing comprises providing the same with a central well 54 which is closed by the upper end 55 of the housing. The closure 55 defines an aperture 56 as shown in Fig. 9 for receiving the guide B and wires C, with shoulders 57 extending into the opening 56 fordisposition between the wires and the ribs on the guide. The opening 56 slidably receives the guide and extractor wires which may be threaded therein, but the shoulders 57 prevent rotation of the guide and wires relative to the housing without accompanying longitudinal movement.

The guide B shown in Fig. 8 secures a transversely disposed ring 58 which slidably engages the walls of the bore 54. Thus, upward longitudinal movement of the guide .8 relative to the bushing A is limited by engagement of the ring 53 with the top of the bushing and downward longitudinal movement of the guide is limited by engagement of the ring 58 with a cover 60 which closes the well 54 at the bottom of the housing. The Cover 60 has a central aperture similar in all respects to the aperture 56 in the top of the housing. After the guide has been disposed within the housing, the cover 60 is placed over the open bottom end of the housing and brazed or otherwise secured thereto.

The tool shown in Fig. 8 is operated similarly to the tool shown in Fig. 1, the housing being provided with angularly related outer surfaces to accommodate a wrench or similar tool. However, when the housing is rotated to effect loosening of the drill section, the extractor wires are held down by applying force to the cap 52. The shoulders 57 prevent relative rotation of the parts during turning movement of the housing.

In connection with the various modifications described, it should be understood that it is not necessary to engage the lower extremities of the extracting wires C with the bottom of the cutting tip of the broken drill section in order to loosen and remove the section. However, to facilitate the lifting operation after the drill section has been loosened, each of the extractor wires may be provided with a radially inwardly facing lip or hook 62 as shown in Fig. 10. It is doubtful that the hook or lip 62 will engage over the cutting edge of the tip of the drill before the drill is loosened but such engagement can be effected after the drill is loosened by twisting or rotating the extracting tool and at the same time pressing the wires downwardly. Thereafter, it is a comparatively simple operation in most instances to remove the broken drill section by a straight pull from the drilled hole.

It should be understood in connection with the operation that the guide provides a support for directingthe extracting wires onto the drill section. In addition, the guide prevents radial displacement of the wires as the tool is utilized to effect loosening of the drill. However,

it is not necessary to construct the guide along the lines of a drill, the guide if desired 'may be fabricated from a flat strip 64 by merely twistnig the strip as shown in Fig. 11 so as to provide spaced spiral flutes 66 separated by spiral ribs 68. With either guide construction, the wires are fully guided and encased to prevent deformation thereof during operation.

The aforedescribed extracting tool if properly operated will greatly facilitate the removal of broken and embedded drill sections and can be used with equal facility to remove similar articles, as, for example, auger bits and taps provided with spiral flutes. Obviously, a single tool constructed in accordance with the present invention will not remove all of the diiferent sizes of drills, but a single extracting tool can be utilized to withdraw a plurality of drills which vary in size within a limited range. For example, an extracting tool having a quarter inch diameter guide can be used to extract broken drill sections ranging in size from one-fourth inch-to approximately five-sixteenth inch.

An extracting tool constructed according to the present invention for removing smaller drills of the'order of oneeighth inch or the like may be modified for greater effectiveness by changing the cross-sectional configuration of the extracting wires. A preferred construction of the wire for drills of this order is such that the cross-sectional configuration is ovate rather than circular so that the flute of the drill section will be substantially filled by the wire. Thus, the rotative forces on the extracting wires will be most efliciently transmitted to the drill section to effect extraction thereof. In this connection, it should be understood that such construction is not restricted for use with relatively small drills, but can be equally well utilized with drills of larger diameter.

It should also be understood that an extracting tool for removing straight fluted taps and the like can be constructed in accordance with the present invention. In such construction, the extracting wires are not spirally wound and the guide is provided with straight flutes. In other respects, the construction is identical with the previously described constructions.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made Without departing from the scopethereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted'as illustrative and not in a limiting sense.

said guide member being arranged to slidably receive in its flutes the pair of spirally wound wires, said guide and said wires being slidably disposed in said bore whereby said housing can be positioned over the drilled hole and said wires and guide extended thereinto, said guide engaging the top of the drill section and said wires engaging the drill section along the flutes thereof, and means on said housing engageable'with said pair of wires and said guide member to prevent relative movement of said housing, wires and guide member whereby operating forces rotating said housing will eflect rotation of the drill section.

3. An extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising a housing having a longitudinal bore and a longitudinal slot intersecting said bore and splitting one end of said housing, a pair of elongated spirally wound wires,

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

We claim as our invention:

1. An extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising a housing having an open ended bore, a pair of elongated spirally wound wires, a guide member having a pair of spiral flutes and corresponding spiral ribs, said guide member being arranged to slidably receive in its flutes the pair of spirally wound wires, said guide and said wires being slidably disposed in said bore whereby said housing can be positioned over the drilled hole with the guide member extending into the hole into close proximity with the .drill section and with said wires engaging the drill section along the flutes thereof, and means on said housing engageable with said pairs of wires to prevent relative movement of said housing and said wires, whereby operating forces rotating said housing will effect rotation of the drill section. v

2. A11 extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising a housing having an open ended bore, a pair of elongated spirally wound wires, an elongated guide member having a pair of spiral flutes and corresponding spiral ribs,

an elongated guide member having a pair of spiral flutes and corresponding spiral ribs, said guide member being arranged to slidably receive in its flutes the pair of spirally wound wires, said guide and said wires being slidably disposed in said bore whereby said housing can be positioned over the drilled hole and said wires and guide extended thereinto, said guide engaging the top of the drill section and said wires engaging the drill section along the flutes thereof, and means engagable with the split end of said housing to close the same on said guide and Wires to prevent relative movement of said housing, guide and wires, whereby operating forces rotating said housing will eflect rotation of the drill section.

4. An extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising an elongated housing having a longitudinal bore and diametrically opposed longitudinal slots intersecting said bore and splitting one end of said housing, a pair of elongated spirally wound Wires each having an end portionbent radially outwardly from the axis of its spiral, an elongated guide member having a pair of spiral flutes and corresponding spiral ribs, said guide member being arranged to slidably receive in its flutes the pair of spirally wound wires, said guide and said wires being slidably disposed in said bore with the bent end portions of said wires being slidably disposed, respectively, in said opposed slots, whereby said housing can be positioned over the drilled hole and said wires and guide extended thereinto, said guide engaging the top of the drill section and said wires engaging the drill section along the flutes thereof, and collar means embracing the split end of said housing and having means for closing said split end upon said guide and wires to prevent relative movement of said housing, guide and Wires whereby operating forces rotating said housing will efiect rotation of the drill section;

5. An extracting tool as defined in claim 1 wherein the means engageable with the pair of wires and the guide comprises a plurality of set screws carried by the housing in spaced relation longitudinally of the bore, said set screws being movable into said bore to effect engagement with the guide and wires.

6. An extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising a pair of elongated spirally wound wires, an elongated guide member having a pair of spiral flutes and corresponding spiral ribs, said guide member being arranged to slidably receive in its flutes the pair of spirally wound Wires, a housing having a generally cylindrical well, the closed end of said housing having an aperture in communication with said well, said aperture receiving said guide member and said wires in sliding relation, the closed end of said housing defining shoulders extending into said aperture between the ribs on the guide and said Wires, a cover for the open end of said well having an aperture corresponding to the aperture in the closed end of the housing and slidably receiving said guide and said wires whereby said housing can be positioned over the 7 drilled hole and said guide and wires extended thereinto, the guide engaging the top of the drill section and the wires engaging the drill section along the flutes thereof whereupon rotation of said housing will effect rotation of the drill section.

7. An extracting tool for removing embedded sections of broken drills and the like from drilled holes comprising a pair of elongated spirally wound wires entwined about one another in spaced relation, a cap securing the upper ends of said wires, an elongated guide member having a pair of spiral flutes and corresponding spiral ribs, said guide member being arranged to slidably receive in its flutes the pair of spirally wound wires, a housing having a generally cylindrical well, the closed end of said housing having an aperture in communication with said well, said aperture receiving said guide member and said wires in sliding relation. the closed end of said housing defining shoulders extending into said aperture between the ribs of the guide and the wires, a radially outwardly extending ring transversely secured to said guide member and slidably disposed in said well, a cover for the open end of said well having on aperture and shoulders corresponding to the aperture and shoulders in the closed end of the housing and slidably receiving said guide and wires, said guide being longitudinally movable in the housing from a position wherein said ring engages the closed end of the housing to a position wherein said ring engages said cover, whereby said housing can be posi' tioned over the drilled hole and the guide and wires extended thereinto, the wires engaging the drill section along the flutes thereof whereupon rotation of said housing will effect rotation of the drill section.

8. A broken drill extractor comprising a guide memher having opposed spiral flutes in the sides thereof, spiral fingers fitting with said flutes, a holder surrounding said guide member and fingers and retaining the said fingers within the flutes, and means for adjustably securing the said guide member and fingers to the holder.

References Cited in the file of this patent UNITED STATES PATENTS 678,186 Lamacchia July 9, 1901 702,011 Kinvall June 10, 1902 1,331,366 Pesa Feb. 17, 1920 1,593,437 Campagne July 20, 1926 FOREIGN PATENTS 92,100 Sweden Apr. 12, 1938 

